Giants in the Hills:

Fieldwork and Forest Modeling at the Sierra

Study Area in Preparation for the DESDynI Satellite

Mission

Michael Hutson

Terrestrial Ecosystems & The Carbon Cycle

http://www.nasa.gov/centers/langley/news/researchernews/rn_carboncycle.html

• LVIS (Aircraft)• ICESat• DESDynI

0

40

He

igh

t (m

)

0 100Intensity

Cumulative Intensity

0 1.0

25 m

8 km

1 km

Measuring Terrestrial Ecosystems

Hurtt et al 2008

Height-Structured Ecosystem Model (ED)

PlantPhysiology

EcosystemBiogeochemistry

Individual

Vital Rates

Disturbance

andLand UseChange

Regional-ScaleEcosystem

Structure andFluxes

EcosystemPhysiology

Ecosystem Demography

Stand-LevelStructure and

Fluxes

Models 3-D vegetation structure, carbon stocks & fluxes

Hurtt et al 2008

Earlier Work with ED •Study of biotic & abiotic heterogeneity at Hubbard Brook Experimental Forest in central NH

•Updated allometry, ran ED for different elevation bands

•Results: accurately predicted biomass stocks, C flux estimates, identified correct reasons

•“Fine-scale heterogeneity has important implications on the spatial resolution of LIDAR collection and model simulation”

Thomas 2007, Thomas et al in press

The Sierra Field Site:A More Extreme Example

Location: Central California

End-to-end: approx. 30km

Elevation Range: 1215-2454m

Importance of fine-scale climate data:

– Local climate greatly influenced by topography

– Trees very sensitive to moisture levels

Summer 2008 Objectives

• Overall: Develop modeling capabilities for vegetation structure in Sierra study site

• Three components:– help collect new data on vegetation structure– assess need for climate data, find if

necessary– preliminary run of ED model, suggestions for

future development

The Field CampaignCrew: Boston University, University of Maryland

Objectives: ground-based measurements to develop & validate remote sensing metrics of vegetation structure

Selection of sites: pre-existing, within 100m of road, accessible to ECHIDNA team

Measurements taken

subplots: DBH over 10cm, species ID, heights of crown-forming trees, estimated heights of dead snags

center plots: all of above, plus crown height & width, distance & bearing from center, and heights for every tree

ED vs. LVIS: Tree Height

Tree Height

ED LVIS

Mean (m)

16 24

Range (m)

0-35 0-63

= LVIS

= ED

study area canopy heights (2006)LVIS

ED vs. LVIS: Biomass

Bio-mass

ED LVIS

Mean (t/ha)

100 225

Range (t/ha)

0-190 0-1335

= LVIS

= ED

LVIS

Dropping ED’s ResolutionED Height Profile

0

0.05

0.1

0.15

0.2

0.25

0.3

0 3 6 9 12 15 18 21 24 27 30 33

canopy height of patch

prop

ortio

n

patch canopy

LVIS mode ED mean

Height (m) 26 16

Biomass (t/ha) 134 100

Different Species,Different Allometries

• Halliwell, D. H. and M. J. Apps.1997. Boreal Ecosystem-Atmosphere Study (BOREAS) biometry and auxiliary sites: overstory and understory data. Canadian Forest Service Report

• DESDynI field crew – unpublished data

height vs. diameter

0

20

40

60

80

100

120

0 100 200 300 400 500 600

dbh (cm)

he

igh

t (m

)

Sequoiadendrongiganteum

Abies concolor

Pinus monticola

Pinuslambertiana

Picea

Pinus

/ED

Different Species,Different Allometries

http://www.fs.fed.us/ne/newtown_square/publications/technical_reports/pdfs/2004/ne_gtr319.pdf

biomass vs. dbh

0100000200000300000400000500000600000700000

dbh (cm)

bio

ma

ss

(k

g)

cedar/giantsequoiafir

pine

spruce

Next Steps to Refine & Test ED• Update plant functional types to include firs & sequoias

– new allometric data– wood density– leaf traits (longevity, specific leaf area)

• Integrate fine scale climate & soil variability– Obtain high-resolution data– Incorporate

• dropping ED resolution vs. tracking sub-gridscale

• Reincorporate fire module– Assess need– Revise as necessary

• Validate results– Comparison to field data– Comparison to repeat LIDAR data

NASA Relevance

NASA Science Questions• How is the global Earth system changing? • What are the primary causes of change in the Earth system? • How does the Earth system respond to natural and human-induced

changes? • How will the Earth system change in the future?

NASA Research Objective• Quantify global land cover change and terrestrial and marine

productivity, and improve carbon cycle and ecosystem models.

NASA Strategic Goal• To study planet Earth from space to advance scientific

understanding and meet societal needs

ROSES 2008

Thanks to…

George Hurtt, UNH

Justin Fisk, UNH

Ralph Dubayah, UMD

Research & Discover @ UNH

…and many more!

ReferencesBartholome, E., and A. S. Belward. "GLC2000: a new approach to global land cover mapping from Earth observation data." International Journal

of Remote Sensing 26 (2005): 1959-977.

Coops, Nicholas C., Richard H. Waring, and Beverly E. Law. "Assessing the past and future distribution and productivity of ponderosa pine in the Pacific Northwest using a process model, 3-PG." Ecological Modeling 183 (2005): 107-24.

DESDynI. 5 Aug. 2008 <http://desdyni.jpl.nasa.gov/>.

DESDynI field crew – unpublished data

Dixon, R. K, et al. "Carbon Pools and Flux of Global Forest Ecosystems." Science 263 (1994): 185-90.

Dulitz, David J. "Growth and Yield of Giant Sequoia." Proceedings of the workshop on management of giant sequoia (1986): 14-16.

Friedl, M. A. "Global land cover mapping from MODIS: algorithms and early results." Remote Sensing of Environment 83 (2002): 287-302.

Halliwell, D. H. and M. J. Apps.1997. Boreal Ecosystem-Atmosphere Study (BOREAS) biometry and auxiliary sites: overstory and understory data. Canadian Forest Service Report.

Hansen, M. C., and B. Reed. "A comparison of the IGBP DISCover and University of Maryland 1 km global land cover products." International Journal of Remote Sensing 21 (2000): 1365-373.

Hubbard Brook Ecosystem Study. 5 Aug. 2008 <http://www.hubbardbrook.org/index.html>.

Hurtt, George C, et al. "ED & LIDAR." 5 Aug. 2008.

Jenkins, Jennifer C., David C. Chojnacky, Linda S. Heath, and Richard A. Birdsey. Comprehensive Database of Diameter-based Biomass Regressions for North American Tree Species. Rep.No. NE-319. Northeastern Research Station, USDA Forest Service. 5 Aug. 2008 <http://www.fs.fed.us/ne/newtown_square/publications/technical_reports/pdfs/2004/ne_gtr319.pdf>.

Kilgore, Bruce M., and Dan Taylor. "Fire History of a Sequoia-Mixed Conifer Forest." Ecology 60 (1979): 129-42.

Lorentz, Katie. "Humans and the Global Carbon Cycle: A Faustian Bargain?" NASA Researcher News. 12 Apr. 2007. 5 Aug. 2008 <http://www.nasa.gov/centers/langley/news/researchernews/rn_carboncycle.html>.

Mayaux, Philippe, Etienne Bartholome, Steffen Fritz, and Alan Belward. "A new land-cover map of Africa for the year 2000." Journal of Biogeography 31 (2004): 861-77.

Mayaux, Philippe, Frederic Achard, and Jean-Paul Malingreau. "Global tropical forest area measurements derived from coarse resolution satellite imagery: a comparison with other approaches." Environmental Conservation 25 (1998): 37-52.

Research Opportunities in Space and Earth Sciences (ROSES) - 2005. NASA. Science Mission Directorate. Washington, D.C., 2005.

Research Opportunities in Space and Earth Sciences (ROSES) - 2008. NASA. Science Mission Directorate. Washington, D.C., 2008.

Thomas, R. Q. "Consequences of Fine-Scale Heterogeneity for Predictions of the Carbon Cycle Using Lidar Data and a Height-Structured Ecosystem Model." Research & Discover. 5 Aug. 2008 <http://www.eos.unh.edu/researchanddiscover/fellows_05_07.shtml>.

Thomas, R. Q., G. C. Hurtt, R. Dubayah, and M. H. Schilz. "Using lidar data and a height-structured ecosystem model to estimate forest carbon stocks and fluxes over complex mountainous terrain." Canadian Journal of Remote Sensing (In press).

Weatherspoon, Phillip C. "Silvics of Giant Sequoia." Proceedings of the workshop on management of giant sequoia (1986): 4-10.